Lubricant pump



E. W. DAVIS LUBRICANT PUMP Feb. 27, 1951 Filed NOV. 30, 1945 Patented Feb.. 27, 1951 UNITED STATESI PATENT OFFiCE LUBRICANT PUMP Ernest W. Davis, River Forest, Ill.

Application November 30, 1945, Serial No. 631,980

2 Claims.

This invention relates to pumps, and particularly to the type employed for dispensing lubricant including heavy oil or grease from a container in a manner which insures delivery of the lubricant at a considerable pressure enabling it to force its way into bearings against appreciable resistance.

One object of the invention is to provide a new and improved lubricant pump of relatively simple construction and of high efficiency.

Another object of the invention is to provide a lubricant pump in which the outlet is controlled by a valve normally closed by means of a spring and opened by the pressure developed in the pump, but in such a manner that the outlet pressure at which the lubricant is delivered is not reduced by the force of the spring.

It is also an object of the invention to provide a lubricant pump in which the outlet is controlled by a piston valve normally closed by a spring with suiiicient force to shear 01T from the edge of the outlet port any material adherent thereto.

A further object of the invention is to provide a new and improved lubricant pump in which the outlet through which the lubricant is expelled by the force of the plunger stroke is a lateral opening controlled by a slide valve actuated by pressure developed in the pumping action but in such Y a manner that the lubricant is delivered at the full pressure attained in the pump cylinder.

Other objects and advantages of the invention will appear from the following description taken in connection with the drawings, in which the Single figure is a vertical axial View of a lubricant pump embodying this invention, together with conventionally represented driving means and lubricant delivery means therefor.

Lubricant pumps of the type to which this invention relates are designed to extract and deliver lubricant usually from a shipping container, such as a drum, into which the pump itself is preferably inserted and supported near the bottom of the container. As shown in the figure, the bottom ofthe container is represented in section at I and pump cylinder I2 is shown with a termina] fitting I4 at its lower end which serves to close the end of the cylinder I2 and also provides a valve chamber and an outlet .passage through which lubricant is delivered. A plunger I6 is arranged to be reciprocated in the cylinder I2 by a pump rod II connected to any suitable means such as a compressed air motor including a cylinder I8 carried by a support 20 which is disposed over the container. The upper part of the c0ntainer is indicated at I I.

(Cl. 10S-166.5)

The pump cylinder I2 is reduced and provided with threads 22 at its upper end for connection with a supporting tube 24 by which the pump is Suspended from the support 2li and preferably a downwardlylopen bell 26 is secured between the lower end of the tube 24 and the shoulder 2B on the cylinder and extends downwardly therefrom to within a short distance above the bottom wall I0 of the container. The cylinder i2 is provided with one or more inlet ports 3l) near its upper end through which lubricant is drawn into the cylinder I 2 by suction produced by the upward stroke of the plunger I6, and the purpose of the bell 26 is to require that the lubricant in the container shall enter the ports 3Q by flowing around the lower edge of the bell 26 so that as the level of lubricant in the container falls, the lubricant will continue to be available after the level has dropped below the level of the ports 3i?.

The tting I4 includes a passage 32 with an outlet pipe 34 connected thereto and leading upwardly through the support 2B to a boss 36 to which there is preferably connected a iiexible hose 38 and a delivery nozzle 46 of conventional form. The outlet passage 32 extends from a port 42 disposed laterally in the valve chamber 44 which is in effect an extension of the cylinder I2, and the port 42 is controlled by a piston valve 46 slidable axially in the cylindrical valve chamber 44 for opening or closing the port 42. The valve 46 is seated upon a relatively stiff spring 48 pocketed in the valve chamber 44 between the valve member and the lower end of the chamber which forms the closed end of the pump cylinder and said valve is provided with a reduced guide stem 5I) slidable in a bore 52 formed in the lower end of the fitting I4. At theupper end of the bore 52 a shoulder 54 serves as a stop to engage a shoulder 56 on the valve stem for limiting the opening movement of the valve. The valve body 46 is formed with an axially disposed passage 58 and lateral ducts connected therewith providing communication between the interior of the cylinder I2 and the space in the valve chamber 44 below the valve 46. It may -be ,understood that the valve 46 is forced open by the pressure developed by the downward stroke of the plunger in the cylinder I2 and that by reason of the passages 58 and 66 extending through the valve, the eective area on which the pressure operates is the cross-section of the lower portion of the stem 50.

With this arrangement, the inlet ports 3U remain closed by the plunger I6 until it has nearly reached the upper limit of its stroke. This produces a strong partial vacuum in the cylinder l2 so that as the plunger uncovers the ports 30 there is powerful suction exerted upon the grease outside the cylinder and a substantial charge of grease is drawn into it. Then as the plunger descends and closes the ports 30 it builds up pressure in the cylinder I2 but does not at rst expel any grease therefrom. The provision of a relatively stiif spring 4S holds the outlet valve 46 closed until the pressure is suiiiciently high in the cylinder to overcome the force ofthe spring and move the valve 46 downwardly to a position uncovering the outlet port 42, The charge of grease is then driven through the passage 32 and pipe 34 for delivery by way of the nozzle--40..-fAs the plunger I6 reverses its motion and travels upwardly in the cylinder l2, the reductionfof'pressure permits the spring 48. to :,.closethe-valve-G in the initial portion of the upward stroketa'nd thereafter the plunger operates to create a .partial vacuum in the cylinder-'I2 as already noted.

f It will be Iseen that althoughthe pressure jdeveloped in the cylinder l2 serves to'compress the spring 48 in opening the valve-46, this same unit pressure is `delivered through the outlet 42 for expelling the grease through thenozzle 40;- it is not diminished but is merely measured and regulated by the pressure of the spring 4,8.

Thepump canreadily be madel double-acting b y making the pump k rod Il smallerthan the plunger I6 or by inserting at they connection between the plunger and theV pump rod al disc or flange of approximately the lsame diameter as the interior of the casing. 24, and then connecting the pipe 34 into thecasing 24 and connecting the upper end of this casing with the discharge passage in the boss 36. f

While there are shownand described herein but a single embodiment of 'the invention, it is to be understood` that the invention is.; not limited thereto or thereby but may assume numerous other forms and includes all modifications, variations and equivalents comingwithin thescope of the appended claims.

I claim:

1. In a lubricant one end, the closed end having a bore of substantially smaller diameterthan that ofthe cylinder, a plunger reciprocable through the opposite end of said cylinder to perform a vsuction stroke away from said closed end anda pressurefstroke toward saidV end of the cylinder, said cylinder `pumpa cylinder' closed at having an inlet port remote from its closed end, said port being uncovered by the plunger to admit lubricant to the cylinder during completion of the suction stroke and lbeing closed by the plunger in the initial portion of the pressure stroke, said cylinder having an outlet passage leading from a port disposed laterally in the cylinder near its closed end, valve means controlling said port comprising a piston slidable in the'cylinder over said port, and a spring seated in the closed end of the cylinder and reacting against said piston valve to hold it normally in position to cover said port, the valve having a portion extending through the bore at the closed end of the cylinder, said valve also having a passageth'rough it leading to the space in which said spring is located,

2."An outlet valve for a pump cylinder comprising,.abody having axially aligned communieating bores of different diameters extending through it, means for securing the body to the discharge end of a pump cylinder incommunication with the large bore of the body, an outlet port extending laterally from the large bore, a piston valve slidable in the large bore and havinga portion lccated at all times in the smaller bore and closing the latter, said valve havinga port providing communication at all times between the outer end of the large bore and the space between the valve and the smaller bore, and a spring exerting a force on the valve to move it toward the open end of the large bore and normally holding it in position closing the. outlet port, ERNEST W. DAVIS.

REFERENCES CITED VThe following references are of record -in 4the le of this patent:

UNITED s'rATEsPATENTs Number Name Date l 880,638 Dickey Mar. 3, 1908 1,041,375 Thompson etal. Oct. 15, 1912 1,844,668 McGregor Feb. 9, 1932 1,962,549 Bjorklund June 12, 1934 2,221,763 Ginter Nov. 19, 1940 2,253,152 ToWler et al. Aug. 19, 1941 2,253,926 Anderson et al. Aug. 26, 1941 2,298,920 Barks et al.A Oct. 13,1942 2,364,550 Pelouch Dec. 51944 

